Was it in 1802 when he discovered his hearing problem _____ Beethoven realized that his future ______ in composing music?

He didn’t make ______ clear when and where the meeting would be held.

We shouldn’t spent our money testing so many people, most of _____are healthy

 The dam will generate electricity _____ about 40 million tons of coal without causing so much air pollution.

It was decades ago ________ I was in my teens ________ the Chinese government decided to reform the social economic system.